Along with /u/restricteddata and /u/imanauthority, I more or less answered this in a thread a couple years back.

I'll adapt the relevant parts of it.

First, by that point pretty much all of the senior Nazi leadership was either captive or dead, so the Nuremberg literature can provide a pretty good idea of what the ones who were still alive were thinking. That said, it's also important to remember that the actual details of the bombings were fairly closely held for years beyond immediate death tolls and (to an extent) surface damage. About the last people in the world who were privy to the more gruesome aspects to it were those awaiting trial in Germany.

By and large, what the restriction of data (sorry, I couldn't resist!) led to among most strategic thinkers for a few years after the war was the use of atomic weapons as merely a much more powerful and compact version of the strategic bombing that had already defined World War II. The imprisoned Nazi leadership certainly fell into this category, and had no problems comparing the Allied raids carried out by Spaatz and Harris' air forces to their own crimes, far lesser in their minds:

Frank to Rosenburg: "They are trying to pin the murder of 2,000 Jews a day in Auschwitz on Kaltenbrunner—but what about the 30,000 people who were killed in the bombing attacks on Hamburg in a few hours?—They were also mostly women and children.—And how about the 80,000 deaths from the atomic bombing in Japan?—Is that justice too?"

Where the atomic bomb came up more often was in the grand view of politics the leadership continued to assess from afar, where most of their interest was in what the development of the bomb would do to US-Soviet relations:

Ribbentrop had his first good laugh in several weeks at the reviewer's comment that Bullitt is in favor of using the atomic bomb "to scare the pants off Russia." As Ribbentrop translated the comment that Russia was only waiting to develop its own atomic bomb to attack us, Goering replied expansively, "Why, of course, every child in the street knows that— anybody who has the slightest political knowledge ... I give them about 5 years' time."

They did not talk about it very much in my presence, but from their smug grins, it was easy to see that they received no small delight from this sign of tension between America and Russia.

This was also - give or take - the relative position of the few people in Nazi leadership who had some idea about their own atomic weapon development, which was that with a focus on plutonium, it wasn't likely to be something that might affect the outcome of the war, but it had a good chance if it succeeded of determining the balance of power after it.

Of those at Nuremberg, only Speer was a member of that group from the spring of 1942 onwards when he transferred out Heisenberg and his group from the Education Ministry to Goering's (relative) oversight and kept some tabs on what they were doing. He had a far less sanguine view of what might happen down the road,

Speer turned from his defense to warn the world of the destruction we might expect in a future war: radio-controlled rockets, aircraft flying at supersonic speed, and atomic bombs, destroying everything within reach; chemical and bacteriological warfare snuffing out all life that remained.

However, even in the extensive interviews with Sereny and his extensive writings, we don't really see him expressing much of a feeling that Germany had dodged a bullet. It's more that he felt the world faced a much heavier caliber one than it had ever dealt with before.

All this said, there were those outside the immediate leadership that expressed opinions on it that should be taken with a grain of salt, but as best as we can tell, the bottom line is that the highest leadership didn't really consider it much worse than what had already happened to them anyway.

Sources: GM Gilbert, Nuremberg Diary Goldensohn, Nuremberg Interviews Sereny, Albert Speer: His Battle with Truth Rose, Heisenberg and the Nazi Atomic Bomb Project